Thermoelectric wine cabinets are a kind of electric appliance or small biomimetic wine cellar designed by simulating natural storage conditions of wine, and are different from those usual wine cabinets for displaying wine. Generally, the thermoelectric wine cabinets have an internal thermostatic environment. In the prior art, an internal power supply is provided to an AC/DC circuit inside the thermoelectric wine cabinet, and may be easily damaged due to the fact that the wine cabinet subjects to a long-term use under energized condition and to influence of high temperature and a large current. Thus, there is still a possibility that the internal power supply is easily damaged whether a new internal power supply is provided to replace the original one or whether the original one is maintained. Further, when the internal power supply is maintained, the thermoelectric wine cabinet is required to be dismantled. For those who do not know the internal configuration of the thermoelectric wine cabinet, it is complicated to assemble the dismantled wine cabinet, thereby to cause secondary damage to the configuration of the thermoelectric wine cabinet. Even for those professional servicemen, repeated dismantlement of the thermoelectric wine cabinet may also cause varying degrees of damage to devices inside the wine cabinet, and the maintenance is very inconvenient.